Proliferative lesions found in rat kidneys after a single dose of cisplatin.

Proliferative lesions in inbred F344 rat kidneys were studied at 6 and 15 months after a single injection of 6 mg cisplatin [CAS: 15663-27-1; cis-diamminedichloroplatinum (ll)]/kg body weight. Solid or cystic lesions developed from altered proximal tubular epithelial cells. The lesions affecting the renal proximal tubules had both granular (organelle-rich) and clear (organelle-poor) variants. These altered cells retained microvilli and contained numerous lysosomes, mitochondria, and abundant rough-surfaced endoplasmic reticulum and free ribosomes. In addition, papillary hyperplasia was seen at 15 months and involved the epithelium lining the renal papilla. The hyperplastic changes of the papillary epithelium were morphologically similar to those produced by other drugs.